Develop Reference

Android Device not recognized by adb

My Android device isn't recognized by eclipse nor adb anymore.
My OS is Windows 7 64-bit, and I'm using a Nexus 4 with Stock Android 4.4.2.
Here are some details on the problem:
Yesterday I could run Android Projects from eclipse on my device with no problems. The only thing that I did on eclipse, which could have caused this problem, was installing the v7 appcompat support library from a resource to eclipse using this guide on developers.android (https://developer.android.com/tools/support-library/setup.html).
The device is still recognized as a normal multimedia drive in Windows when it's not in debug mode.
The device is in Developers mode and in Debug mode when I try to run an Android Project in eclipse or try to see if it's recognized by adb using adb devices in the console.
The Google USB drivers have been installed through the ADK Manager
The USB OEM drivers for Windows have already been installed according to the tutorial on the android-developers site (see: https://developer.android.com/tools/extras/oem-usb.html)
I tried to restart adb by using the commands adb kill-server and adb start-server, and again checked if the devices was recognized by using adb devices. The device was still not listed on the console.
Restarting windows & eclipse did not fix this problem.
What's the solution to this problem?
UPDATE: Thanks for the replies, the problem is solved (for now).
I tried the following suggestions in this order:
I restarted my device - this did not fix the problem
I set my device to PTP mode - this fixed the problem.
So I reset my device to MTP mode & debug mode again to check if it still would be recognised by adb for some reason. It definitly doesn't get recognised by adb when it's in MTP-mode. I don't know how it got recognised some days ago, because I never setmy device to PTP-mode. Anyway, the solution to my problem is that my Nexus 4 must be in PTP-Mode and of course in debug-mode to get recognised by adb.
I didn't try any other suggestions since my problem got solved with my current drivers.

Generally, I think your USB connection should be set to use MTP (Media Transfer), however, I couldn't get my computer to recognize my device (Nexus 4). Oddly, setting the USB connection to Camera got it working for me.

I recently had this issue (but before that debug over wifi was working fine) and since none of the above answers helped me let me share what I did.
Go to developer options
Find Select USB configurations and click it
Choose MTP (Media Transfer Protocol)
Note: If it's set to this option chose another option such as PTP first then set it to MTP again.
UPDATE:
PTP stands for “Picture Transfer Protocol.” When Android uses this protocol, it appears to the computer as a digital camera.
MTP is actually based on PTP, but adds more features, or “extensions.” PTP works similarly to MTP and is commonly used by digital cameras.

I also faced the same problem and tried almost everything possible from manually installing drivers to editing the winusb.inf file. But nothing worked for me.
Actually, the solution is quite simple. Its always there but we tend to miss it.
Prerequisites
Download the latest Android SDK and the latest drivers from here. Enable USB debugging and open Device Manager and keep it opened.
Steps
1) Connect your device and see if it is detected under "Android Devices" section. If it does, then its OK, otherwise, check the "Other devices" section and install the driver manually.
2) Be sure to check "Android Composite ADB Interface". This is the interface Android needs for ADB to work.
3) Go to "[SDK]/platform-tools", Shift-click there and open Command Prompt and type "adb devices" and see if your device is listed there with an unique ID.
4) If yes, then ADB have been successfully detected at this point. Next, write "adb reboot bootloader" to open the bootloader. At this point check Device Manager under "Android Devices", you will find "Android Bootlaoder Interface". Its not much important to us actually.
5) Next, using the volume down keys, move to "Recovery Mode".
6) THIS IS IMPORTANT - At this point, check the Device Manger under "Android Devices". If you do not see anything under this section or this section at all, then we need to manually install it.
7) Check the "Other devices" section and find your device listed there. Right click -> Update drivers -"Browse my computer..." -> "Let me pick from a list..." and select "ADB Composite Interface".
8) Now you can see your device listed under "Android Devices" even inside the Recovery.
9) Write "adb devices" at this point and you will see your device listed with the same ID.
10) Now, just write "adb sideload [update].zip" and your are done.
Hope this helps.

It may sound silly but in my case the USB cable was too long (even if good quality). It worked with my tablet but not with the phone.
To check this, if you run on Linux run lsusb to make sure that your device is at least officially connect to the usb port.

Try use PdaNet. you can download it from here
It installs missing drivers when you plugin your device.
Obviously make sure you "debug usb" option in "developers options" is on.
Another thing, it's important to uninstall any device's installed driver before using it.

Fundamentally, the issue has to do with not being able to get MTP+ADB working while for example PTP+ADB may work. In my case when I plugged Nexus 5, windows 7 will install only MTP driver completely ignoring ADB. I couldn't find a good solution for this problem anywhere else so here I provide steps (some of the steps I copied from other sources):
0) Unplug Nexus 5. Make sure you selected MTP and ADB.
1) Make sure that sdk\extras\google\usb_driverandroid_winusb.inf in Google SDK had the following lines (in two places in that file):
;Google Nexus (generic)
%CompositeAdbInterface% = USB_Install, USB\VID_18D1&PID_4EE2&MI_01
NOTE: VID_18D1 is Google VID, PID_4EE2 is PID for MTP+ADB, MI_01 means that ADB is on interface 1 (MTP is on interface 0).
You can check what is on what interface by plugging Nexus 5 into a Linux system and typing lsusb.
2) first delete all installed Google USB drivers. One good tool is called USBDeview and can be find at the following location:
http://www.nirsoft.net/utils/usb_devices_view.html
Download the tool and run it (there is no need to install it). Take a look at the colored status indicator on the far-left of the USBDeview window. Green indicates the the device functions properly. Pink means the device can unplug and works properly (although it may not actually work properly). Red indicates a disabled USB device. Gray (circled, below) means the device is installed, but not connected.
Second, remove all gray items with the words “Google”, “Linux”, “ADB”, or “Android” in the title.
3) Now delete old cached Google *.inf files. Open a Windows Explorer and navigate to the C:\Windows\INF directory. Somewhere in there there is an "oemN.inf" file (where N is a number that will vary on your system) that is a copy of the android_usb.inf -- the thing to do is to find which file and remove it. Windows keeps a cache of the INF files here and what we found is that sometimes an older cached copy is used instead of a newer version.
One simple way to find which one using the Windows Explorer:
- In the explorer's Search box, enter "androidwinusb86.cat" without the quotes.
- Typically the search will be empty because no filename has this pattern.
- Go to Tools/Folder Options, click Search Tab and click Always search file name and contents. Click Apply
- Search again. This time it should list a few files such as "oem90.inf" (you'll have one or more, with different numbers).
Now use the Windows Explorer and delete the "oemNN.*" files that matched above (only those with androidwinusb in them.).
4) We now want to disable installation of MTP by windows before windows discovers ADB. Now search for wpdmtp.* files in the same directory. Presence of these files will force install MTP disregarding ADB class in the same (composite) device. Move these files out of \inf folder
5) plug in the device again. This time, both MTP and Android ADB driver installation will fail.
6) Find Other devices in the Device Manager and when expanded it should show Nexus 5 and MTP. Right click and update Nexus 5 by navigating to the sdk\extras\google\usb_driver\android_winusb.inf.
Move wpdmtp.* files back to \inf folder. Right click MTP device and update.
7) If necessary, confirm on your Nexus 5 that this PC has access to the phone.
8) If everything went as expected you should see in Device Manager the following:
Expand Android Device. Right click Android Composite ADB Interface, select Properties, choose tab Details, under Property select Hardware Ids. You should see USB\VID_18D1&PID_4EE2&MI_01
Expand Portable devices. Right click Nexus 5, select Properties, choose tab Details, under Property select Hardware Ids. You should see USB\VID_18D1&PID_4EE2&MI_00

With USB connected, on android device Settings > Developer options > Revoke USB debug authorizations USB Debug. Remove the USB and connect again, then "Allow USB debugging".

For those people to whom none of the answers worked, try closing the chrome://inspect/#devices tab in Chrome if it is open. This worked for me.

Go to prompt command and type "adb devices". If it is empty, then make sure you allowed for "MTP Transfer" or similar and you enabled debugging on your phone.
To enable debugging, follow this tutorial:
https://www.kingoapp.com/root-tutorials/how-to-enable-usb-debugging-mode-on-android.htm
Then type "adb devices" again. If a device is listed in there, then it should work now.

Set your environmental variable Path to point to where the adb application is at: [directory of sdk folder]\platform-tools

Enabling Developer mode by tapping on Build Number 7 times worked for me.

Make sure you are connecting with a USB and not a lightning cable. I had this problem trying to connect using a cord with lightning cables on both ends and it would not list the device. But switching to a USB to lightning cable worked.

Check that the USB cable is indeed capable of transferring data. Some cheaper ones, especially those meant to charge non-phone/computer devices, might only support charging.
You can verify this by checking if the device shows up as mountable file system. In Linux, you can also use the command lsusb to check if it's being detected.

Find drivers for your device and install them
That will be the end of your device not detected problems
Windows have driver problems, sometimes messed by overriding the existing driver
You can also try uninstalling driver from Win7 and reinstalling

For those facing problem after upgrading their android device to android 10, same PTP Mode option will work as prescribed by user3135185

I tried all these, but nothing worked. Finally, I changed my old data connection USB-c cable, to a new one. Maybe with updates of windows/android studio, the older USB-c protocols are no longer recognized for transfer.

Download and install Moborobo software on your computer.
Connect your device with USB debugging through USB cable.
Now open moborobo and it will connect to your android.
Stay connected, now your device should recognize as adb devices and get
listed.

Unable to install the Android USB driver on Windows 7

So I want to use my new Nexus 5 for debugging my apps.I tried to install the Android USB driver via the device manager
But my nexus is listed as portable device and uses the default windows driver.How can I replace the windows MTP-USB driver with the android driver?When I click update driver software und select "\sdk\extras\google\usb_driver", it tells me that the driver software is up-to-date.
Edit:
USB Debugging is already activated
Edit 2:
Sorry my fault there are actually two Nexus 5 in my Device Manager. The other one accepted the android driver.

First you'd want to make sure you device is in 'debug mode' or 'usb debugging' - set through development settings in your phone's 'system settings'
then run adb devices from your adt-bundle folder/platform-tools to see if it got your device.
Edit:
if it doesn't work try, from your 'drivers' tab-
Update Driver -> Browse for driver software on my computer -> Let me pick from a list of device drivers from my computer -> Have Disk -> Navigate to your usb_driver folder
Notice the extra step near the end, you don't submit the folder in the "Browse for driver software on my computer" tab

download this usb driver: http://dlcdnet.asus.com/pub/ASUS/EeePAD/nexus7/usb_driver_r06_windows.zip
go to the device manager , right click the nexus device and choose properties, choose "hardware" and then choose update your driver , choose manualy and pick the folder you opend the zip file to and press apply.
open your setting in nexus . go to : "about the device" , at to the bottom of the page and press it strong text7 times .
open the developers menu and enable debug with usb.
finally press storage from the setting menu and click the menu that apears at the top left corner. press the connect usb to the computer, choose the second option (PTP).
that should do the trick.

The way I got the drivers installed for my nexus 5 was by following these instructions but I had to turn off my phone and do the steps below but for following the first set of instructions for the link below:Nexus 5 Driver installation instructions
power off your phone.
press and hold Volume Down and Power buttons simultaneously
- an Android robot will show up and the Fastboot Mode text is listed.
connect the Nexus 5 to your PC via USB Cable.
After doing this the drivers installed but had a yell warning sign. However I was still able to get it to take commands and for it to be seen by the ADB devices command. I currently am using windows 7, and I have the adb setup in my environment variables so I can run commands from the command line.
In the command line before you call the adb devices, make sure you navigate to the android platform tools folder '\Android\android-studio\sdk\platform-tools then from here call the adb devices and you will know for sure if your device is being detected!

Just to highlight the key step that solved the problem for me using a Nexus 5.
Follow the steps by Neeraj, just replacing the first one by the drivers in http://developer.android.com/sdk/win-usb.html
Key point is to make sure you change the usb connection to use PTP and try to install the driver from the Nexus 5 under other devices.
That solved the issue for me.

Another related issue:
Every time you connect a device through USB 3.0, Windows 7 automatically installs its own drivers that can't be updated. Removing them does nothing, as they will just be immediately installed again upon reconnection.
To get get around this, you need just need to use a USB 2.0 slot.

To allow usb debugging for an lg f60 d390 in Android Studio I had to install LG PC Suit.

I had same issue, Uninstall the existing driver. Then your device will be listed under Android Device -> Composite ADB interface in device manager. You then can follow steps to update the Google - USB driver.

This answer worked for me.
Switch the USB port you use.
For whatever reason once I did this Windows recognized my device.

adb doesn't show nexus 5 device

Android Studio 0.3.6
Fedora 18 3.11.7-100.fc18.x86_64
Nexus 5 Kitkat
Hello,
I have been using my Samsung Galaxy Tab 3 7.0 running Android 4.1.2 everything works fine with adb.
However, I have just bought a new Nexus 5 device, and when I do the following command adb devices it doesn't show my Nexus 5.
Under Android SDK Manager | Extras | Google USB Driver | status "Not compatiable with Linux"
Because I am running Fedora 18 if I need drivers what drivers for the USB do I need?
Because the Samsung works fine and I can deploy and run my apps, I think my setup is correct. So I am wondering if there is something wrong with my Nexus 5.
I have tried the following:
adb kill-server
adb start-server
Setting the Nexus 5 Camera PTP and media device MTP didn't work.
Many thanks for any suggestions,

I had a similar problem with my Nexus 4(Android version 4.4.2), it wasn't listed in adb devices.
Make sure USB debugging is enabled from device, and do the following on your PC:
Update Android SDK (Google USB Driver)
From PC Control Panel, System -> Device manager -> Right click Nexus 4 -> Update driver.
Set android-sdk-folder\extras\google\usb_driver as path to search, include subfolders checked.
If windows tells you that the driver is up to date, just uninstall the driver (right click on nexu4 -> uninstall driver) and start from step 2 again.
After that, open a cmd and type adb kill-server and then a adb devices, now it will include your device.
https://developer.android.com/studio/run/oem-usb.html

Follow these steps,
Enable Developer options in your device. To enable the developer mode, Settings->About phone, tap Build number option 7 times continuously
Go to Settings-> Developer options and Turn on USB debugging
Make sure you reconnected the device via USB and grant permission on the dialog that appears.
From the above steps it didn't work try this step, Go to Settings->Security and turn on Unknown Sources

What you need to do is this:
Settings | About Phone
Scroll to the bottom to build number.
Tap on build number about 7 times. Each time you will get a popup message saying you are x steps away from being a developer
When you get to the final step you will get a message saying now you are a developer
Go back into settings and you will see a new setting Developer options there you will see a lot of options for developers. Enable USB debugging
Re-connect you phone to the usb, and you should see you device under adb devices.
I hope this answer helps someone else.

This simple steps worked for me, I debug on my Nexus 5 and 5X devices on Windows 8.1.
The steps to follow are these:
1) Enable from Developers Options the Debug USB Mode
2) Unplug the device from the computer
3.1) Go to Settings → Storage, in the ActionBar, click the option menu and choose USB computer connection.
3.2) If you didn't find the 3.1) option then go to Settings → Developers Options → Select USB Configuration.
4) Select Camera (PTP) connection.
5) Plug the device and you should have a popup on the device allowing you to accept the computer's incoming connection, or something like that.
6) If it doesn't work try to toggle the Debug USB Mode in the Developers Options
Finally, you should see it now in the DDMS and voilà.

My windows solution:
Go here and download and unzip to an easy location:
http://developer.android.com/sdk/win-usb.html#top
Right click 'My Computer' or 'Computer'
Select properties
Select Device manager
Look for your device. It should have a yellow mark above it.
Click 'update driver software'.
select browse my computer for driver software.
select the usb_driver folder you saved earlier.
install it
and wala. magic.

For those who are still frustrated, if you are using the experimental ART runtime, try switching back to dalvik (in developer options on device)

Here is simple solution for Windows 7 and Nexus 5 on Android 5.
Download the Nexus 5 Drivers from http://androidhost.org/jelry
Extract the zip contents and place all files in a single folder on your desktop.
Connect your device to your computer.
Launch the Device Manager on your PC.
Now you should see the Nexus 5 listed in the hardware list.
Right-click the ‘Nexus 5′ line and then click on Update Driver Software.
Next, click the ‘browse my computer’ option.
In the new window click on ‘Browse…’ button.
Go to folder unzipped at step 2. Select the folder where you extract the USB Drivers. Click Next. – make sure to tick the subfolder box too.
Now, the Windows installer will search for Nexus 5 drivers, click Install when asked for permission.
Wait for the process to complete and then check the Device Manager list to confirm that the installation was successful.
Original: http://www.android.gs/download-and-install-google-nexus-5-usb-drivers-adb-fastboot/
Note: do not forget to enable USB debugging on your device :)

Something nobody has mentioned yet:
Some cables do NOT support data. I was sitting here wondering why my Nexus 5 was refusing to show up on OSX. It turned out I was using a cable that didn't support data.
I swapped to a different cable which did support it, and suddenly I was able to use USB debugging.

If anyone is trying to connect Nexus 5 to a formatted Windows XP then follow these steps:
Download and install media transfer protocol porting kit:
MTP porting kit
Download and install WMFDistributable-11 for XP:
WMFDist-11 XP
Download and install LG United Mobile Driver v3.10.1:
stackoverflow is not allowing to share more than 2 links, please google this.
Connect your device.
Go to Device Management
Right click on Nexus 5 and click Update Driver
Select Yes this time only
Select Install Software Automatically
Wait for sometime.. and enjoy transferring files

ADB and driver versions matter. The newer the device, the lower the chances of an older version ADB to work correctly.
Apps using their own ADB copy need to be updated or at least have their ADB updated manually.
When installing Helium / Carbon for instance, it uses an old / incomplete ADB. Newer devices might not link to the ADB server for this very reason.
What I'm writing here should work for any future devices on Windows and possibly *nix OSes.
First the systems must be prepared.
on Android:
activate developer mode, either from an app (like Helium, when prompted) or by accessing the about phone section, taping build number until the developer mode unlocks
in developer settings enable USB debugging
in security settings allow unknown sources
(when connected with USB cable) set USB connectivity to PTP mode (camera device, if so labeled)
in Windows:
uninstall older USB driver (with file removal) if there is one, but only when the device is connected and in developer mode, otherwise
that particular device won't be listed
install latest USB driver after the device has been plugged in and developer mode is active, the device will be listed as unknown or other in Device Manager; the drivers can be downloaded separately from Google Android support site, these are the same as vendor drivers, with only fewer ID's in inf file making the driver not being recognized for all Android devices
if the driver does not recognise the device, no problem, install it generically: Manual Install > Show All Devices > Have Disk > pick inf location of the Android USB driver and from the list select Android ADB Interface; there's not need to edit the inf by adding hardware ids, the end result is the same
each of the modes, PTP and MTP will have their own driver entry, so if the device asks for MTP, the same driver installation procedure must be followed, again
Once these steps are/were previously done correctly, adb must be tested.
If Android SDK was installed previously, open a command prompt where adb.exe is
and test the listing of the device.
adb start-server
IMPORTANT NOTE: This command will prompt the device to allow the communication between the computer it's been linked to on the first run. The prompt will also list an RSA key specific to the PC in question. Without this prompt on start-server, ADB will NOT work! Nor will any application relying on ADB.
adb devices
Must list the device(s). If the list is empty, and most likely the RSA prompt did not occur, then no communication will work. If the list is empty the current ADB (and SDK) must be updated or installed fresh (in the case of apps bringing in their own ADB runtime, like Helium / Carbon).
In the case of applications that do bring their own ADB, if the version is old, and these apps insist in using it instead of the SDK one, these files need to be replaced with the latest ones from Android SDK. Plain and simple copy & paste.
As for Android SDK, the only required packages to be installed are SDK Tools and Platform-tools. There, ADB.exe will need some support libraries, on Windows these files are AdbWinApi.dll and AdbWinUsbApi.dll. After all is done, the SDK can be uninstalled from SDK Manager while being able to retain the ADB tool if this is the only runtime used, depending on the case in question.

After doing all steps like enable debug, ... I had to put a sim card and reboot the phone

Solution for Windows 7 and Nexus 5 (should be applicable for any Nexus device):
I figured out that my system was installing the Nexus 5 default driver for windows automatically the moment I was connecting my Nexus 5 to my system through USB. So uninstalling the default driver was in vain and it gets installed automatically anyways.Moreover if you uninstall the default driver, you won't be able to locate Nexus 5 under Devices in Computer Management. So here is what i did and worked for me!
Computer-->right Click-->Manage-->Device Manager-->Portable Device-->Nexus 5-->Update Driver Software
Choose 'Browse my computer for driver software'
1.Make sure to give this location: %APPDATA%\Local\Android\sdk\extras\google\usb_driver
Click Next and you are done.

I have suffered the same issue and was able to solve it by simply changing on my Android device (Nexus 5X) in Developer options > Select USB Configuration to RNDIS (USB Ethernet)

For those trying to connect their android phone in adb with no luck and have tried every USB configuration (MTP, PTP, RNDIS). It is worthing noting that in my case with my Nexus 5X on Windows 7 I successfully connected the phone to adb only by choosing the Charging USB Configuration. With any other configuration (MTP, PTP, ...) it doesn't work.
USB Driver: Google USB Driver v11
ADB Version: Android Debug Bridge version 1.0.39

Madx's answer is a strong hint. Now I can make MTP work for my Ubuntu 20 and Nexus 5X (Android 8) device. MTP is an easy solution in Windows for smartphone users. However, to me and many Ubuntu/Linux users, current Ubuntu/Linux MTP tools "LOOK" messy and unstable for Android devices, e.g. No folder is shown for android phone in Nautilus.
Delving deeper I find it might be a security enhancement done by GOOGLE in the Android device/phone side. Direct internal data access remains a privilege for the developers. And one needs to set/reset MTP as a developer for Android device in order to make Ubuntu MTP tools work. There is nothing wrong with Ubuntu/Linux MTP tools.
The steps for MTP data access are an extension to Madx's answer:
(For Android device) Enable from Developers Options the Debug USB Mode.
Unplug the device from the computer.
3.1) Go to Settings → Storage, in the ActionBar, click the option menu and choose USB computer connection.
3.2) If you didn't find the 3.1) option then go to Settings → Developers Options → Select USB Configuration.
4.1) Select MTP connection.
4.2) Select Camera (PTP) connection.
4.3) Select MTP connection again. (This refreshs GOOGLE MTP protocol stack, I guess)
Plug the device and you should have a popup on the device allowing you to accept the computer's incoming connection, or something like that.
If it doesn't work try to toggle the Debug USB Mode in the Developers Options
And now file folders are shown up for N5X device in Nautilus.
Are these too much? There might be a bug in Android MTP implementation, and 4.2) & 4.3) are steps to WAKE Up Android MTP stack:-)
As a kind reminder, Windows and FTP are the last resorts for MTP.

Try executing :
sudo ./adb kill-server
sudo ./adb start-server
sudo ./adb devices

In my case:
The phone was connected as a media device.
Clicked on that message and got a menu. "USB computer connection"
In that menu chose to connect it as a camera (for devices that do not support MTP)
And then it worked.

Oh boy, I spent 3 hours for this simple thing and tried combination of above instructions.If it doesnt work for you, just try several combinations of above instructions and it will. I am on windows 7 and nexus 5. Issue I had was when I try to install driver from the google usb folder, windows 7 fails to install. Here are my steps:
-first uninstall all nexus drivers on windows 7. connect with USB cable, go to device manager and uninstall the driver; unplug the cable and repeat until no drivers are found and nexus shows up under "other devices" in device manager. I also configured nexus device as camera (PTP)
-follow #Dharani Kumar instructions. They make appropriate configuration changes for nexus device
-follow #Harshit Rathi instructions. They will ensure eclipse can show the device when windows detects the device
-unplug and replug the USB cable after a minute. Now you should see a pop up on nexus device. click it so that windows 7 will allow installing the driver from your local system. if you dont see this, restart your device or pc
-follow #Rick's instructions.you can download USB driver as listed by #jimbob
If you still have a problem, re read this entire thread and go from there (I spent hours on other web sites; those bits and pieces didnt help)

Go here and download and unzip to an easy location:
http://developer.android.com/sdk/win-usb.html#top
Download and install

I had the same problem, USB debugging enabled, device showing up in windows but I never got the question about RSA fingerprint when I connected my Nexus (6) device, nor did it show up in the Android Device Manager.
BUT
In the windows device manager I did have an entry saying it was an android device and Composite ADB interface etc. Still didn't work.
When I tried the previous tips about manually updating the drivers, Windows 8.1 just responded that "Windows has determined that the driver software for your device is up to date" this was not true. Looking at the driver details I saw that the driver was published by "ClockworkMod". I realized this must be because I had installed the Helium app sometime last year. So I uninstalled that, still had the same problem. Checked again, this time it was indeed google drivers, but version 7 published in 2012 (and not version 11 published 2014). I uninstalled these AS WELL and then tried the trick of reinstalling the driver from the SDK located in:
%localappdata%\Android\sdk\extras\google\usb_driver
Now when I replugged my device it finally works and can be debugged with Android Studio.
Indeed a driver problem.

Answer by Rick and MadX is the right way to do the steps (Thumbs Up for the answer)
In my case I am using
Akcess USB Type C Data Sync Cable For Nexus 5x, 5P - White
As Nexus 5x do not supply type C to usb cable I purchased it from some vendor.
Having the same issue. What I am doing stupidly is:-
I am connecting the cable in wrong way. After I reconnect it from upside down its working for me.
I might think that some of the Cables do not support debuggable. But its in my case.
This(Image) is my case the Type C should be as USB side symbol. A stupid solution, but work for me

ADB not recognising Nexus 4 under Windows 7

I'm running on Windows 7, and I've updated all the drivers as it says on the Android developer website regarding using hardware devices. However, Eclipse is still not recognising my Nexus 4 when I try to run the application. The Android device chooser pops up, but it doesn't show anything on the hardware section. I've turned debugging, third-party apps, and mock locations all on on my phone as well.
Is this because the phone is still new? Is there a way of making my Nexus work with Eclipse?
Nothing is showing up under ADB devices in the command prompt.

I had a similar sounding situation with my Nexus 4. For me it was an issue with the drivers Windows was installing automatically. I followed the instructions in [Q]Computer won't recognize phone? - Post #8. I had some slight differences on Windows 7.
For me I,
Uninstalled the driver from Device Manager
Let it automatically install the generic 'MTP device driver'
Right clicked on the new device and selected 'Update Driver'
Selected 'Have Disk' and pointed it to [android-sdk-dir]\extras\google
Watched an 'ADB' driver install.
Opened Eclipse to successfully run on my Nexus 4.

Just to confirm a previous comment. I needed to switch my connection to Camera (PTP) mode in addition to enabling Developer options and then selecting USB Debugging from the newly appeared Developer Options.

To enable USB debugging, go to settings, about phone and then at the bottom tap build number seven times. This will enable the developer settings where you can enable USB debugging.

To fix/install Android USB driver on Windows 7/8 32bit/64bit:
Connect your Android-powered device to your computer's USB port.
Right-click on Computer from your desktop or Windows Explorer, and
select Manage.
Select Devices in the left pane.
Locate and expand Other device in the right pane.
Right-click the device name (Nexus 7 / Nexus 5 / Nexus 4) and select Update
Driver Software. This will launch the Hardware Update Wizard.
Select Browse my computer for driver software and click Next.
Click Browse and locate the USB driver folder. (The Google USB
Driver is located in <sdk>\extras\google\usb_driver\.)
Click Next to install the driver.
If it still doesn't work try changing from MTP to PTP.

I had the same problem, but I didn't want to change to PTP mode. This is how I fixed it with MTP still enabled.
Uninstalled Google USB Driver from Eclipse in the Android SDK Manager.
Uninstalled the driver from Device Manager - click box for "delete driver from my computer"
Unplugged and re-plugged my phone into the computer.
Windows "improperly" installed drivers for the Nexus 4.
The Nexus 4 was now showing up in My Computer like a drive.
Reinstall Google USB Driver in SDK Manager.
Update Nexus 4 driver in Device Manager.
Everything works.

I had the same problem and none of the above worked, but the following solution worked for me:
On my Nexus 4:
Go to Settings
Choose Developer options (from the end of the list after pressing seven times on "About phone")
Check the "USB debugging" and press OK.

For what it's worth, in my case I was able to fix the problem simply by changing my USB connection mode from Media device (MTP) to Camera (PTP).

I had to resort to a clean install of Windows 7 x64 to fix this issue.
I tried all steps/variants in the other answers. No luck. Device Manager would show my 'Android Device / Android Composite ADB Interface' working properly with the 7.0.0.1 driver from Google, but nothing could get 'adb devices' to show my Nexus 4.
I used USBDeview to uninstall every USB device that had connected to my computer except my keyboard and mouse. No luck.
I enabled 'Show hidden devices' in Device Manager and uninstalled anything related to USB. No luck.
I added Google's vendor ID to adb_usb.ini. No luck. I deleted adb_usb.ini and ran 'android update adb'. No luck.
I brought my Nexus 4 to my brother's apartment to confirm it wasn't faulty. Worked on his machine without a hiccup.
I'm glad the clean install worked, because further troubleshooting was going to require swapping motherboards or buying a MacBook.
Boy, that escalated quickly.

Changing USB mode from MTP to PTP worked for me.

How to do it on Windows 8 (I think, it will work for Windows 7 too)
Open Android SDK Manager and delete Google Usb Driver
Open Control Panel -> Devices Manager -> Find your Nexus -> right click -> delete device
Unplug your device
Open Android SDK Manager and install Google Usb Driver
Connect your device
Open Control Panel -> Devices Manager -> Find your Nexus -> right click -> update drivers -> Manual update -> open android-sdk folder (enable checkbox for subfolders) -> install driver from Google Inc
adb kill-server; adb start-server; adb devices should show your nexus
Do not forget, that Android 4.2 now want you to submit RSA key from your computer, look at your device screen.
To enable developers options on Android 4.2: Open Settings -> About phone -> Tap on Build Number 7 times.

Just to add to the above posts for anybody struggling to get their Nexus 4 recognized by Eclipse - ADT. In the past the device was recognized by Eclipse ADT without any issues!
I ran into the same problems as the original question. Every approach I tried wouldn't work...
Toggling "USB debug" selection
Toggling "Allow 3rd party" apps selection
Allowing Mock locations
Reinstalling driver
Restarting adb.exe
Simple solution in the end
Go to Settings -> Storage -> USB Computer Condition (Menu option from Storage Screen)
Change from Media Device (MTP) to Camera (PTP)

You need to install USB drivers only if you use Windows (If you're using MAC/Linux, most likely it will work fine without any driver installations)
in the following link they describe how to do it:
http://developer.android.com/tools/extras/oem-usb.html
In short:
Connect your Android-powered device to your computer's USB port.
Right-click on Computer from your desktop or Windows Explorer, and select Manage.
Select Devices in the left pane.
Locate and expand Other device in the right pane.
Right-click the device name (such as Nexus S) and select Update Driver Software. This will launch 6. the Hardware Update Wizard.
Select Browse my computer for driver software and click Next.
Click Browse and locate the USB driver folder. (The Google USB Driver is located in \extras\google\usb_driver.)
Click Next to install the driver.

My symptoms were the composite device (this contains all of the actual USB devices such as the ADB interface, camera, etc) was not being installed. This has a hardware id of:
USB\VID_18D1&PID_4EE6&REV_0228
USB\VID_18D1&PID_4EE6
The composite device's children will have &MI_## after them. If you see those, then this is not the same issue.
I resolved this by coping usb.inf to %windir%\inf from a virtual machine of Windows 7. The hardware detected and installed fine after.

I have 2 Nexus 4 devices. One was connecting to ADB without any problems, the second one never showed up when I used the adb devices command. An additional symptom was, that the second phone did not show up as a portable device in Windows Explorer when the phone was set to Media mode.
At some point I found that a temporary solution for the second Nexus was to switch it to PTP mode. Then it was found by the adb devices command. The weired thing was that the first phone worked in both modes all the time!
Finally I found this solution that now allows me to connect both phones in both modes:
set USB mode of the phone to MTP (Media)
Using PC device manager uninstall the device ->Android Device ->Android ADB Interface
Make sure to check the box "Delete the driver software"!
then set the USB mode of the phone to PTP (Camera)
Using PC device manager uninstall the device ->Portable Devies ->Nexus 4
Then unplug the USB and plug it back in (ensuring that its set to MTP (Media) and I found that the device was correctly registered in Device manager as a ->Portable Devies ->Nexus 4
Solution found at: http://forum.xda-developers.com/showthread.php?p=34910298#post34910298
If you have a similar problem to connect your Nexus to ADB then I recommend to first switch it to PTP mode. If your problem vanishes with that step, I recommend to go through the additional steps listed above as MTP will probably be the mode you will want to set your phone to most of the time.

Follow Google's instructions for this, OEM USB Drivers.

In case none of the answers work perhaps the following clarifications will help. I followed the top answer and tried to load the program with ADB from the command line to reduce the possible complications and this did not work.
Once enabling PTP mode the ADB devices command would find my Nexus 4, but I could not push to it. I had to use Eclipse and in order for the dialog to display to accept the RSA key described below.
Note: When you connect a device running Android 4.2.2 or higher to your computer, the system shows a dialog asking whether to accept an RSA key.

On Windows 7, with Samsung Nexus S, it showed nothing in Device Manager, the adb devices command showed no devices, but when plugged in device said USB debugging was on and connected.
I used Andrea's Feb 2 answer to install the Google USB driver, which created the /gooogle/usb_driver directory and used RobertNovelo's Mar 7 answer to go to the link and follow the instructions. The device showed up in Device Manager under 'other'. I right clicked on it and selected update driver, and now it shows up in Device Manager under 'Android device', and now command line adb devices lists it.

I had a similar problem, and none of the previous solutions worked for me, and I've just solved it by myself (after a few hours of frustration), so I'm going to share my solution.
My computer suddenly stopped recognizing any Android device I've plugged in after it installed Android Composite ADB Interface for my Nexus 4. I was not able to uninstall the driver, because any attempt to do so by Device Manager was unsuccessful (Device Manager stopped responding every time).
So I've solved it this way:
Switch Windows into safe mode
Uninstall Android Composite ADB Interface
Install old SAMSUNG Android ADB Interface
Switch Windows into normal mode
Plug-in Android device (Nexus 4 in my case)
Windows recognized the device as Nexus 4
Install driver from android-sdk/extras/google folder
Everything works again! :)

I have a way to fix your problem:
Download Nexus Root Toolkit v2.0.4: http://www.wugfresh.com/nrt/
Install and select your diver and choose the Google API. For example, I chose Nexus 4 and selected Google API 4.4.4
Click "full driver installation guide..." and click step 3 tab. Choose the Google drivers.

My Windows 7 installation was not finding a driver at all. The xda-forums post has the right folder to tell Windows where the drivers are -- {SDK directory}/extras/google/usb-driver.
If you don't have the extras/Google folder + Tim Bellis, go to the SDK Manager in your IDE and look for the Google USB driver in the Extras category, and install it. I cannot tell you how to do this in Eclipse, but if you have IntelliJ IDEA, it's near the bottom of the list, checkmark it and click "Install packages".

(Windows 7) My solution to this was to find the device in Device Manager, uninstall the existing driver and install a new one from the android folder in your user account using the include subdirectories option.
All the best.

Some of you may have experienced this issue. If you don't find the USB driver (like me, I downloaded a bundle of Eclipse and the Android SDK), go to <sdk>/SDK Manager. Open it and select USB Driver from the options to install and you are ready. I had to do the PTP mode too.

If you have problems to install the ADB driver under Windows 8.1, try this solution: ADB Driver and Windows 8.1

For me, it was Nexus 4 and Windows 7. I reinstalled the drivers, changed to PTP - basically went through everything.
Clicking the tab that said MainActivity.java rather than activity_main.xml in Eclipse fixed it for me.

My solution is very silly. I had tried all the solutions above and wasted so many hours. Then I found out the solution when I browsed developer options. I didn't check mark the "USB debugging" option. The silly me assumed turns on developer options mean turns on USB debugging, but I was wrong.

It was a driver missing problem with me. I had enabled the USB debugging, tried changing the USB cable, tried reinstalling the Google USB drivers, but nothing came to my rescue.
Then ultimately I downloaded the device drivers as suggested here.
To make sure whether you have a device driver problem, go to:
Computer->right click
Manage
Device Manager
And see if you have your Nexus shown as an "Android device" or as a device in "Others".
If it shows in "Others", your problem should be resolved by downloading & extracting this and then following these steps:
Right click on your device after finding it in Device Manager as per the above mentioned three steps.
Say Update driver software.
Say Browse My computer for driver software
Pinpoint it to the location where you had downloaded the drivers from the above link.
Finally, your device will show up as follows:
As soon as you do this, a popup will show up on your device asking for permission to debug. Once you accept, you are ready!

Device not detected in Eclipse when connected with USB cable

I want to run my Android project on a device.
My device is not detected in Eclipse when I connect it with a USB cable.
I restarted Eclipse and I have checked that USB debugging is on, on the device.
Can anybody tell me what the problem is and how to resolve it?

Before starting, Make sure that USB DEBUGGING IS ENABLED in your phone settings !!!
1) BASIC STEP - Plug in device via USB, then go to device page in Android developers blog. There you can find necessary information regarding adding USB vendor ids. Add your device specific ids, and restart eclipse if needed.
2)If you were able to see the device connected(using command: 'adb devices'
) earlier, but not anymore, then just try restarting ADB. (you can use the commands: 'adb kill-server' followed by 'adb start-server'. adb commands need to be executed from platform tools folder in the Android SDK, if you havent exported it).
3)If neither of them works out and you are on windows machine,
then check the installed usb drivers are correct. If not install proper drivers
Please find more information on how to install/update drivers in http://developer.android.com/tools/extras/oem-usb.html
If this also is not working, try installing Universal ADB windows driver https://plus.google.com/103583939320326217147/posts/BQ5iYJEaaEH
4)You may also try increasing the timeout time
Go to preferences-> android->DDMS in eclipse, then try increasing 'ADB connection timeout(ms)' value
Update based on newer answers:
5)Run > Run Configurations > Target. Please make sure, the option "Always prompt to pick device" is enabled.
Special case: Windows 8 and Nexus 10 (from this question: ADB No Devices Found)
Windows 8 wouldn't recognize my Nexus 10 device. Fixed by Setting the
transfer mode to Camera (PTP) through the settings dialogue on the
device.
Settings > Storage > Menu > USB Computer connection to "Camera (PTP)"

I solve this problem by updating PC portable device drivers:
Go to : Settings -> Applications -> Development to enable USB debugging
Plug in device USB
Desktop "My Computer" right click -> "Manager"
Choose "Device Manager"
Portable Device
right click on your device -> "Update Driver software" -> Search automatically (wait about 3-5min, )
Done

Restarting the adb server, Eclipse, and device did the trick for me.
C:\Android\android-sdk\platform-tools>adb kill-server
C:\Android\android-sdk\platform-tools>adb start-server
* daemon not running. starting it now on port 5037 *
* daemon started successfully *
I had the same problem as mentioned on this question.

I had similar problem, drivers was okey, but Eclipse did show me the device in Run > Run Configurations > Target tab. But I checked the option "Always prompt to pick device". And then running the application from Eclipse the prompt window finally showed my device.

After a long and frustrating search, finally I made my Micromax Funbook p362 to connect with eclipse and made it to suit for development.
*Installed Moborobo (All in one Android smart phone management tool).
*Perform stop -server / start -server using ADB.
*Reboot the device.
*Restart the eclipse.
*Device got detected.(Eclipse - list of adb devices)

In addition to the steps provided by #asfsafgsf (above), make sure to re-enable your phone's developer modes/functions. For my Motorola Atrix:
settings>applications>Unknown Sources: allow 3rd party apps
settings>applications>Development: to enable USB debugging, mock locations, and disable phone sleep
A note on developer modes
USB Debugging is the main mode you will need for running apps through eclipse when your phone is connected via usb (obviously). Disable phone sleep is also handy for self-explanatory reasons.
Allowing 3rd party app sources allows you to beta test your app on a larger-scale. With this, you can host your own apk and instruct your beta-testers to download it (prior to releasing it to the Google Play storefront). More specifically, 3rd party support allows the installation of android package files that don't contain a google approved signature (required for play store hosting). With 3rd party apps enabled, a handset will be able to run packages regardless of their source. You should also be able to receive an APK via bluetooth and install it in this mode.

You can also list all currently connected devices by running the following command:
adb devices

Go to http://developer.android.com/tools/extras/oem-usb.html#InstallingDriver and follow the steps on the android website but on browsing for the USB folder don't use the directory specified -> ((sdk)\extras\google\usb_driver). (sdk) just means your sdk location.
Your phone should have the correct driver and it can be accessed when you plug it in and go to the CD Driver in My Computer, in my case it's G:\drivers\adb_driver. Use this directory instead and it should work. (It may be differ with devices).

One possible reason is to check Android SDK Manager and install Google USB Driver in Extras folder if you have not installed it.
Following the steps here: http://developer.android.com/sdk/oem-usb.html#InstallingDriver allowed Eclipse to display the device.

Do following steps to detect your device in eclipse : -
On Mobile Side:- For Connect USB sync, your Android device needs to have USB Debugging enabled.
To enable Android USB Debugging Mode do following steps :-
Android 2.x - 3.x devices:
Go to Settings > Application > Development > USB Debugging.
Android 4.x devices:
Go to Settings > Developer Options > USB Debugging.
For devices running Android 4.2.2 or later, you may need to unlock Developer Options before it is available within the Menu:
Go to Android home screen.
Pull down the notification bar.
Tap "Settings"
Tap "About Device"
Tap on the "Build Number" button about 7 times.
Developer Mode should now be unlocked and available in Settings >
More > Developer Options or in Settings > Developer Options
On PC side
Connect your device to the PC with USB cable.
Download Google USB Driver
Extract/Unzip “latest_usb_driver_windows.zip” file on your computer
(using 7-zip free software, preferably)
Open device manager on your PC
Windows 7 & 8 users → search for
Device Manager from Start (or Start screen) and click to open.
Windows XP users → Google it
You will see list of all devices attached to your computer in the
device manager. Just find your device (it’ll most probably
be in the Other devices list with a yellow exclamation mark by the
name of ADB devices), then Right-click on it and select Update
Driver Software.
Select “Browse my computer for driver software” in the next window
Now click the “Browse…” button and select the “usb_driver” folder
that we extracted in Step 3 from “latest_usb_driver_windows.zip”
file.
Do NOT select the zip file, select the folder where the
contents of the zip file are extracted. And keep the Include
subfolders box checked
During the installation (as a security check) Windows may ask your
permission to install the drivers, click “Install”
Once the installation is complete you’ll see a refreshed list of
devices on the Device manager screen showing your phone’s driver
installed successfully.
Now in eclipse do following steps to install your app in your device:-
Go to Run > Run Configurations > Target tab.
Check option "Always prompt to pick device". And then running the
application from Eclipse,the prompt window finally showed
your device.

Please check whether your device is shown in the Eclipse device tab in Window > Open Perspective. If its not shown there then you need to install drivers for the the device. Once the device is visible in the Devices tab then change the launch settings for manual target. Once you launch your app then it will allow you to choose from the real device or the virtual devices

If you have the following problem
Then you can so following to fix it
Note : You should enable USB debugging on your android device(It will be in developer option in System settings)

I had this problem. With my galaxy S2. So came here for advice, but couldn't find anything specific. Then I found this 'Kies' software on the Samsung site, under the section for my exact model of phone, under downloads, after clicking software.
It installed the right USB drivers as part of the process of installing Kies and so my phone instantly then became visible on eclipse.
The Kies version for Galaxy S2 (GT I1900) = http://www.samsung.com/uk/support/model/GT-I9100LKAXEU-downloads#
There are other versions of Kies for other android models of course.

(new) device not showing, Check List:
Developer Option ON
USB debugging ON
Try changing to USB Storage/MTP/PTP
if it installs Window driver and fails, there's your problem (verify in Windows Device Manager) fix it.

ok this is an old thread -
but I spent nearly two days and did not get anywhere
Here is what solved my problem
I had USB debugging enabled ( finding developer options itself was a pain - I think the 7 times tap from google is childish and just plain stupid - rant over )
However HTC syn manager , eclipse ADT and windows computer management were all unable to identify my device
My problem was my phone was set to ONLY USB Charge - this was the problem
In 'USB Computer connection' >> Choose the option USB Storage
Once you do this - PC will install drivers and your device will get detected by Eclipse as well as in 'Computer Management' under ''Android USB devices '
Now I still dont know a way to access ''USB Computer connection' but at that time I did get the option to change and t worked
For those ( like me earlier ) who dont know how to identify if 'Computer Management' shows their device look for 'Android USB devices '
If its present - then your device is being detected by your PC
Hope this helps some others
shankar

On a kitkat Google Nexus 7, I tired everything here, and did not succeed. The device did previously connect properly to this computer.
Then I hit settings - developer-options - Revoke USB debugging authorisations
and confirmed that I really did want to revoke them.
I unplugged and plugged the USB. The tablet beeped and asked if wanted to authorise the computer for debugging. I said "Yes" and everything worked again.

For me the problem is with Defective USB Cable. I have tried those above all answers. Nothing gives me any fix. But finally i came to know the problem is because of my usb cable while changing the usb cable. While connecting through the usb cable the phone is charging but the drivers are not installed. Some usb cable don't have the option for that. So while buying check it and buy.

Best approach is install PDA net(software) on both system as well as in android device. This software automatically installs global driver for all phones, provides easy connectivity to android device.
Follow these links to download
For system
http://pdanet.co/
For android device
https://play.google.com/store/apps/details?id=com.pdanet&hl=en

Here is my checklist in windows (not the device itself) when my device is not shown:
Make sure "USB debugging is turned in setting>Developer options.
Check status bar on your device. It tells you if your phone is connected as Media Device (MTP) or Send images (PTP). My device is only listed when PTP is selected.
Turn of windows firewall.
Turn of any proxy programs ran on whole windows ports.
And finally stop adb.exe from windows task manager and wait some seconds to restart automatically.